A hybrid vehicle is a vehicle using two or more different kinds of power sources, and is generally a vehicle that is driven by an engine that obtains a driving torque by burning fuel and a motor that obtains a driving torque with battery power.
The hybrid electric vehicle is provided with a gasoline engine or a diesel engine. In the diesel engine hybrid electric vehicle, an exhaust gas recirculation system to reduce exhaust gasses and a turbocharger to improve power performance may be mounted on the diesel engine. Particularly, an air control valve (ACV) to reduce vibrations of the vehicle should be provided at the diesel engine.
In the diesel hybrid electric vehicle, vibrations of the engine are generated by combusting fuel injected into the diesel engine after an ignition key is turned off. In order to prevent such vibrations of the engine, the diesel hybrid electric vehicle controls an opening of the air control valve and blocks intake air to prevent combustion.
In addition, the opening of the air control valve is adjusted to maintain an appropriate temperature when a diesel particulate filter (DPF) which reduces exhaust gas is operated.
However, exhaust gas sucked into a manifold may cause soot which includes particles due to incomplete combustion, and the soot may accumulate at the air control valve. In this case, an inlet of the air control valve may narrow according to the accumulated soot.
In the conventional art, an amount of air inflow is adjusted without learning the opening of the air control valve because the air control valve is a new product. However, if the inlet of the air control valve narrows as described above, the air control valve may not be operated precisely and emissions regulations may not be satisfied.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.